Precipitation of AMP Carbamate in CO2 Absorption Process

This work presents a novel concept for CO2 absorption with an amine solution forming a precipitate when absorbing CO2. The systems consist of the sterically hindered amine, 2-amino-2-methyl-1-propanol, and an organic solvent, N-methyl-2-pyrrolidone or triethylene glycol dimethyl ether. The precipitate is formed when CO2 is absorbed and reacts with the amine. In order to design an absorption process using precipitating solutions, detailed knowledge on when and where the precipitate will form is needed. The onset of precipitation in four different amine solutions has been investigated in this work, and the composition of the precipitate was also determined using NMR spectroscopy.